Electrical terminal

ABSTRACT

An electrical terminal interconnecting two conductive members which includes a threaded opening extending from a surface of one of the members and a resilient elongated conductive strip having spaced legs with one leg connected to the second conductive member and the other leg having latch means cooperating with the thread to releasably lock the second conductive member to the first conductive member.

United States Patent Wolf Aug. 8, 1972 [54] ELECTRICAL TERMINAL FOREIGNPATENTS OR APPLICATIONS [72] Inven r: W l r A- f, 0g n p 29,506 12/1909Great Britain ..339/74R Assigneez Switches Incorporated Switzerland R[22] Filed: Dec. 18, 1970 Primary ExaminerJoseph H. McGlynn [21] Appl No99 393 Att0rney-Dressler, Goldsmith, Clement & Gordon [57] ABSTRACT 2 l.{2 y g g i i i An electrical termmal lnterconnectlng two conductive [58]Field 223 252 members which includes a threaded opening extend ing froma surface of one of the members and a resilient elongated conductivestrip having spaced legs with one leg connected to the second conductive[56] References cued member and the other leg having latch means UNITEDSTATES PATENTS cooperating with the thread to releasably lock the 3 193795 7/1965 K hb 1 339/252 second conductive member to the firstconductive re 1e b 2,126,494 8/1938 Means ..339/74 R mm 6 2,191,2972/1940 Olson ..339/252 R 10 Claims, 8 Drawing Figures PATENTEnAus 819723.683.316

FIG.5

lNVENTOR WALTER A. WOLF ATTORNEYS ELECTRICAL TERMINAL BACKGROUND OF THEINVENTION The present invention relates to an improved electricalterminal for connecting a wire to a conductive member.

In the manufacture of various circuitry, it becomes necessary tointerconnect two conductive members of various types. The most commontype of permanent.

connection utilized in electrical circuitry is to solder two memberstogether to provide a permanent connection between the members. However,it many instances it becomes necessary to provide some type ofreleasable connection between two conductive members.

For example, in the automobile industry numerous connections must bemade between two conductive members which can readily be separated incase of the need for repair or replacement of either of the members orother associated structures.

While various types of releasable connections for electricallyconductive members have been known for years, the auto industry is atall times striving to reduce the cost of manufacturing and assemblingthe various components of an automobile. Because of the number ofvehicles being manufactured annually, a savings of a fraction of a pennyin the manufacture or assembly cost for any part results in aconsiderable annual savings.

While various types of releasable terminal connectors are known theseare too expensive to construct and/or are complicated to incorporateinto existing structures. In addition, the less expensive types ofterminal connectors do not positively interconnect the two members.

Thus, the auto industry, as well as other industries, is continuallystriving to design terminal connectors that are less expensive whilestill performing the intended function.

SUMMARY OF THE INVENTION The present invention provides a simple andinexpensive electrical terminal for connecting the conductive wire to alarger conductive member. The terminal includes a specially designedclip that is connected to the wire and cooperates with a threadedopening in the larger conductive member.

More specifically, the connection includes an elongated sheet metalstrip which is reversely bent upon itself approximately at the center toproduce two spaced legs interconnected by a bight portion and one of thelegs has connecting means for connecting ,the wire thereto. The oppositeleg has a locking ledge defined intermediate the ends thereof. Thelocking ledge is defined by a planar portion extending from the bightportion and an arcuate portion merging with the free end of the planarportion to produce a ledge.

The two conductive members are interconnected by grasping the ends ofthe legs remote from the bight portion and forcing them towards eachother to allow the strip to be inserted into the opening. Once the clipis fully inserted, defined by projections extending from opposite sidesof the first leg, the legs are released and the inherent resiliency ofthe strip will force the locking ledge into engagement with a surface ofthe groove the thread.

The positive locking action between the strip and the threaded openingresults from the combination of the angle of inclination of the threadsurface relative to the longitudinal axis of the opening as well as theacute angular relation of the first or planar portion of the leg havingthe locking ledge defined thereon. In addition, the circular nature ofthe threaded opening and the flat nature of the locking ledge will causethe opposite edges of the locking ledge to bite into the surface of thethread between the minor and major diameters to positively lock thestrip into the threaded opening. In fact, a pulling force tending topull the wire away from the other conductive member will increase thelocking action of the strip within the opening. This arrangement assuresthat the two conductive members can only be separated by applying apositive force to the free leg adjacent the opening and force the legstogether to disengage the locking ledge from the thread surface in theopening.

BRIEF DESCRIPTION OF SEVERAL VIEWS OF DRAWINGS FIG. 1 of the drawingsdiscloses an exemplary environment for the terminal of the presentinvention;

FIG. 2 is an enlarged sectional view of the steering column shown inFig. 1;

FIG. 3 is a plan view of the electrical connector be fore the conductivemember is connected thereto;

FIG. 4 is a side elevation view of the electrical connector;

FIG. 5 is an end view of the connector as viewed along line 5-5 of FIG.3;

FIG. 6 is a perspective viewof the connector;

FIG. 7 is a fragmentary plan view of the connector inserted in thethreaded opening; and

FIG. 8 is an enlarged fragmentary view showing the locking ledge and thethread in the opening.

DETAILED DESCRIPTION While this invention is susceptible of embodimentin many different forms, there is shown in the drawings and will hereinbe described in detail one specific embodiment, with the understandingthat the present disclosure is to be considered as an exemplification ofthe principles of the invention and is not intended to limit theinvention to the embodiment illustrated.

The illustrated environment for the electrical terminal of the presentinvention is disclosed in FIG. 1 as an automobile steering mechanismgenerally indicated at 10 and including a steering column 12. A hub 14is fixedly secured by a nut 18 (FIG. 2) to a shaft 16 ex tending throughthe steering column 12 while a steering wheel 20 (FIG. 1) is mounted onthe hub by means of spokes 22.

In many commercial automobiles, the steering wheel 20 incorporates aswitch for completing the circuitry to various auxiliary equipment, suchas a horn. Thus, the first portion of the switch (not shown) is suitablygrounded by a wire 24 while the second portion of the switch isconnected to a source of current (not shown) through a wire 25. Since itmay become necessary to remove the steering wheel 20 and the hub 14 fromthe steering column for repair or replacement, it is desirable to have areleasable connection for the wires adjacent the upper end of thesteering column.

According to the present invention, the electrical terminal forconnecting the conductive members 14 and 24 provides a means forpositively securing the two members while allowing separation by meremanipulation of parts. Furthermore, the electrical terminal is extremelyinexpensive since it includes only one element and a threaded hole.

In the illustrated embodiment, the electrical terminal includes anelectrical connector or clip specifically designed and configured tocooperate with a threaded opening in a manner to positively lock theconnector in the opening while allowing easy removal by merely graspingthe clip at the appropriate locations and applying pressure thereto.

As more clearly illustrated in the drawings, particularly FIG. 2, theelectrical terminal includes a threaded opening 30 defined in oneconductive member, the hub 14, and an electrical connector or clip 32carried by the second conductive member or wire 24. The electricalconnector 32 is more clearly shown in FIGS. 3 through 6 and includes aresilient, elongated conductive sheet metal strip which is reverselybent upon itself to a substantially U-shaped configuration to definefirst and second spaced legs 34 and 36 interconnected by a bight portion38. The first leg 34 has means 40 on the free end thereof to define aconnection for the wire 24. Since the wire 24 includes a conductiveelement 24a enclosed in a sheath of insulation 24b, it is desirable toprovide a fixed connection for both the conductive element and thesheath. Thus, according to one aspect of the invention, the connectingmeans 40 includes a first clamping member 42 and a second clampingmember 44. The first clamping member 42 includes spaced arms 46 whichextend upwardly from the main body portion of the leg 34 and which areadapted to be crimped around the conductive element or wire 24a, as isshown in the assembled condition in FIG. 2. Likewise, the secondclamping member 44 includes a pair of arms 48 extending upwardly fromthe main body of the first leg 34 and the arms 48 are adapted to becrimped around the sheath of insulation 24b. With this arrangement, boththe wire and the sheath are securely fixed to the electrical connector32.

According to the primary aspect of the present invention, the second leghas latch means defined on an intermediate portion thereof whichcooperates with the wall of the opening 30 to secure the conductivemembers together in a manner which will be explained in more detailhereinafter. The latch means on the second leg is defined by a firstplanar portion extending from the bight portion 38 at an acute anglewith respect to the main body of the first leg 34 and a second arcuateportion 52 merging with the free end of the planar portion to produce atransversely extending ledge 54.

It will be noted from an inspection of FIGS. 3 and 4, that therespective legs are flat between opposite edges 60 and 62 and the firstleg 34 has a pair of projections 64 extending outwardly from theopposite edges, for a purpose which will be described later. The flat orplanar transverse configuration of the strip will result in the lockingledge being substantially planar between opposite edges or ends 60 and62, for a purpose which will be described later.

To interconnect the two conductive members 14 and 24, the strip 32 isfirst connected to the wire 24a by crimping the arms 46 about the wire24a and the sheath is likewise secured by crimping the arms 48.

Thereafter, the two conductive members are interconnected by graspingthe two legs 34 and 36 adjacent the ends which are remote from the bightportion 38 and flexing the legs towards each other to allow the strip tobe axially inserted into the threaded opening 30. The extent of axialinsertion of the clip into the opening 30 is defined by the projections64 extending from the opposite edges 60 and 62 of the resilient strip32. These projections engage the upper edge or end wall of the openingadjacent the surface 66 of the conductive member 14. When the electricalconnector has been inserted in the opening the legs are released and theinherent resiliency of the strip causes the locking ledge to engage asurface of the wall of the groove defined by the thread at a locationbetween the major and minor diameters of the thread.

As inspection of FIG. 7 reveals that the transverse dimension of theconnector as well as the locking ledge 54 is substantially less than thediameter of the opening but is substantially greater than the radius ofthe opening 30. With this dimensioning, the latch means or ledge willextend transversely of the axis of the opening as a chordal element andengage the wall of the opening at circumferentially spaced locations.This arrangement will have the opposite ends of the ledge 54 bite intothe wall of the opening.

The configuration of the clip is such that the electrical terminalcannot be separated without grasping the leg 36 and producing a positiveforce towards the first leg 34. For example, if an axial pulling forcewere applied to the wire 24, this pulling force would be transmittedthrough the first leg 34, the bight portion 38'and the first portion 50of the second leg. The locking ledge, in this instance, would act as afulcrum for the acute angled first portion 50 of the leg 36 and theangular relation of the leg to the longitudinal axis of the clip and theaxis of the opening would tend to cause a pivotal movement in aclockwise direction as viewed in FIG. 2 about the fulcrum point 54.Thus, a pulling force on the wire 24 would tend to wedge the firstportion 50 in the opening. Since the ledge 54 extends transverselyacross the axis of the opening and engages the thread at opposite endsalong circumferentially spaced locations on the wall of the opening,such a pulling force would further cause the opposite ends of the ledgeto bite into the wall of the groove defined by the opening and preventaccidental removal of the connector 34.

However, should it become necessary to separate the two conductivemembers, the end portion of leg 36extending beyond the upper surface 66of the conductive member can readily be grasped and the two legs flexedtowards each other to allow the clip to be readily removed without thenecessity of any tools.

While not specifically limited to any dimension, an exemplary relativedimension of the width of the clip and the diameter of the opening maybe on the order of a ratio of 4:5. For example, with a threaded openinghaving a diameter of 0.25 inches, the clip would have a dimension on theorder of 0.20 inches.

As can be appreciated from the above description, the electricalterminal of the present invention, requires only the formation of aconventional threaded opening in one of the conductive members and theat tachment of a specially designed clip to the other of the members.The clip can readily be manufactured by stamping on a mass productionbasis thereby producing a terminal which is very inexpensive tomanufacture and which can readily be assembled without any special skillor tools.

In fact, in many instances where wire is used to ground a circuit, thegrounding member may have an existing unused threaded opening. Insituations this threaded opening could be utilized for receiving theterminal clip. For example, present steering wheel hubs have twothreaded openings that facilitate the use of a wheel puller in order topull the wheel from its splined shaft for replacement or repair work.These threaded openings could be used for a second purpose for providinga ground connection for the horn circuit.

Iclaim:

1. An electrical terminal interconnecting two conductive memberscomprising means defining a circular opening extending from a surface ofone of said members, said opening having a circumferential groove in itswall below the upper surface; a resilient elongated conductive strip,said strip being reversely bent to a substantially U-shapedconfiguration to define first and second spaced legs interconnected by abight portion; means on the free end of said first leg defining aconnection for the other conductive member; and latch means on saidsecond leg, said latch means being located in said groove and engagingthe wall of said groove at circumferentially spaced locations to securesaid conductive members, said second leg having a free end extendingfrom said opening for grasping to release said latch means and allowsaid members to be separated.

2. An electrical terminal as defined in claim 1, further includingprojections extending from opposite sides of said first leg adjacentsaid free end for limiting the extent of insertion of said strip intosaid opening.

3. An electrical terminal interconnecting two conductive memberscomprising means defining a circular opening extending from a surface ofone of said members; said opening having a continuous thread defined inthe wall thereof; a resilient elongated conductive strip, said stripbeing reversely bent to a substantially U-shaped configuration to definefirst and second spaced legs interconnected by a bight portion; means onthe free end of said first leg defining a connection for the otherconductive member; and latch means defining a ledge on said second legand cooperating with a surface of said thread at a location between themajor and minor diameters of said thread and at a location spaced fromthe surface of said one of said conductive members to secure saidconductive members, said second leg having a free end extending fromsaid opening for grasping to release said latch means and allow saidmembers to be separated.

4. An electrical terminal interconnecting two conductive memberscomprising means defining an opening extending from a surface of one ofsaid members; a resilient elongated conductive strip, said strip beingreversely bent to a substantially U-shaped configuration to define firstand second spaced legs interconnected by a bight portion; means on thefree end of said first leg defining a connection for the otherconductive member; and latch means on said second leg and cooperatingwith the wall of said opening at a location spaced from the surface tosecure said conductive members, said second leg having a free endextending from said opening for grasping to release said latch means andallow said members to be separated, said first being substantiallyplanar between said bight portion and said free end, and said second legincluding a planar portion extending from said bight portion and anarcuate portion between said planar portion and said free end, saidplanar and arcuate portions merging in a manner to define said latchmeans.

5. An electrical terminal as defined in claim 4, in which the otherconductive member is a wire enclosed in a sheath of insulation and inwhich said means on the free end of said first leg includes a firstclamping member for connecting the wire to said strip and a secondclamping member connecting said sheath to said strip.

6. An electrical terminal interconnecting two conductive memberscomprising means defining an opening extending from a surface of one ofsaid members; a resilient elongated conductive strip, said strip beingreversely bent to a substantially U-shaped configuration to define firstand second spaced legs interconnected by a bight portion; means on thefree end of said first leg defining a connection for the otherconductive member; and latch means on said second leg and cooperatingwith the wall of said opening at a location spaced from the surface tosecure said conductive members, said second leg having a free endextending from said opening for grasping to release said latch means andallow said members to be separated, said first leg is beingsubstantially planarbetween opposite ends and having projectionsextending from opposite edges adjacent said free end for engaging anedge of said opening to limit the insertion of said strip into saidopening, and said second leg including a planar portion extending fromsaid bight portion at an acute angle with respect to said first leg andan arcuate portion merging with the free end of said planar portion toproduce a ledge defining said latch means.

7. An electrical terminal as defined in claim 6 in which said strip hasa width substantially less than the diameter of said opening.

8. An electrical terminal interconnecting two conductive memberscomprising means defining an opening extending from a surface of one ofsaid members; a resilient elongated conductive strip, said strip beingreversely bent to a substantially U-shaped configuration to define firstand second spaced legs interconnected by a bight portion; means on thefree end of said first leg defining a connection for the otherconductive member; and latch means on :said second leg and cooperatingwith the wall of said opening at a location spaced from the surface tosecure said conductive members; said second leg having a free endextending from said openings for grasping to release said latch meansand allow said members to be separated, said latch means defining aledge extending transversely of the axis of said opening and engagingthe wall of said opening at circumferentially spaced locations.

9. An electrical connector for connecting a conductive wire to a memberhaving a threaded opening therein comprising a resilient elongated stripof sheet metal reversely bent to a substantially U-shaped configurationto define first and second spaced legs interconnected by a bightportion, said second leg having a second leg being planar and saidsecond portion being arcuate and having a convex surface extendingtowards said first leg.

10. An electrical connector as defined in claim 9, and further includingprojections extending from opposite edges of said first leg adjacentsaid connecting means, said connecting means including first and secondspaced clamping members respectively adapted to clamp the wire and aninsulating sheath to said strip.

1. An electrical terminal interconnecting two conductive memberscomprising means defining a circular opening extending from a surface ofone of said members, said opening having a circumferential groove in itswall below the upper surface; a resilient elongated conductive strip,said strip being reversely bent to a substantially U-shapedconfiguration to define first and second spaced legs interconnected by abight portion; means on the free end of said first leg defining aconnection for the other conductive member; and latch means on saidsecond leg, said latch means being located in said groove and engagingthe wall of said groove at circumferentially spaced locations to securesaid conductive members, said second leg having a free end extendingfrom said opening for grasping to release said latch means and allowsaid members to be separated.
 2. An electrical terminal as defined inclaim 1, further including projections extending from opposite sides ofsaid first leg adjacent said free end for limiting the extent ofinsertion of said strip into said opening.
 3. An electrical terminalinterconnecting two conductive members comprising means defining acircular opening extending from a surfAce of one of said members; saidopening having a continuous thread defined in the wall thereof; aresilient elongated conductive strip, said strip being reversely bent toa substantially U-shaped configuration to define first and second spacedlegs interconnected by a bight portion; means on the free end of saidfirst leg defining a connection for the other conductive member; andlatch means defining a ledge on said second leg and cooperating with asurface of said thread at a location between the major and minordiameters of said thread and at a location spaced from the surface ofsaid one of said conductive members to secure said conductive members,said second leg having a free end extending from said opening forgrasping to release said latch means and allow said members to beseparated.
 4. An electrical terminal interconnecting two conductivemembers comprising means defining an opening extending from a surface ofone of said members; a resilient elongated conductive strip, said stripbeing reversely bent to a substantially U-shaped configuration to definefirst and second spaced legs interconnected by a bight portion; means onthe free end of said first leg defining a connection for the otherconductive member; and latch means on said second leg and cooperatingwith the wall of said opening at a location spaced from the surface tosecure said conductive members, said second leg having a free endextending from said opening for grasping to release said latch means andallow said members to be separated, said first being substantiallyplanar between said bight portion and said free end, and said second legincluding a planar portion extending from said bight portion and anarcuate portion between said planar portion and said free end, saidplanar and arcuate portions merging in a manner to define said latchmeans.
 5. An electrical terminal as defined in claim 4, in which theother conductive member is a wire enclosed in a sheath of insulation andin which said means on the free end of said first leg includes a firstclamping member for connecting the wire to said strip and a secondclamping member connecting said sheath to said strip.
 6. An electricalterminal interconnecting two conductive members comprising meansdefining an opening extending from a surface of one of said members; aresilient elongated conductive strip, said strip being reversely bent toa substantially U-shaped configuration to define first and second spacedlegs interconnected by a bight portion; means on the free end of saidfirst leg defining a connection for the other conductive member; andlatch means on said second leg and cooperating with the wall of saidopening at a location spaced from the surface to secure said conductivemembers, said second leg having a free end extending from said openingfor grasping to release said latch means and allow said members to beseparated, said first leg is being substantially planar between oppositeends and having projections extending from opposite edges adjacent saidfree end for engaging an edge of said opening to limit the insertion ofsaid strip into said opening, and said second leg including a planarportion extending from said bight portion at an acute angle with respectto said first leg and an arcuate portion merging with the free end ofsaid planar portion to produce a ledge defining said latch means.
 7. Anelectrical terminal as defined in claim 6 in which said strip has awidth substantially less than the diameter of said opening.
 8. Anelectrical terminal interconnecting two conductive members comprisingmeans defining an opening extending from a surface of one of saidmembers; a resilient elongated conductive strip, said strip beingreversely bent to a substantially U-shaped configuration to define firstand second spaced legs interconnected by a bight portion; means on thefree end of said first leg defining a connection for the otherconductive member; and latch means on said second leg and cooperatingwith the wall of said opening at a location spaced from the surface tosecure said conductive members; said second leg having a free endextending from said openings for grasping to release said latch meansand allow said members to be separated, said latch means defining aledge extending transversely of the axis of said opening and engagingthe wall of said opening at circumferentially spaced locations.
 9. Anelectrical connector for connecting a conductive wire to a member havinga threaded opening therein comprising a resilient elongated strip ofsheet metal reversely bent to a substantially U-shaped configuration todefine first and second spaced legs interconnected by a bight portion,said second leg having a first portion extending from said bight portionat an acute angle relative to the longitudinal axis of said strip and asecond portion merging with said first portion to an angle to define alocking ledge, said first leg having connecting means for receiving theconductive wire, said legs being adapted to be flexed towards openingand the resiliency of said strip causing said locking ledge to engage athread surface upon release of said legs, said first leg being planarbetween said connecting means and said bight portion, said first portionof said second leg being planar and said second portion being arcuateand having a convex surface extending towards said first leg.
 10. Anelectrical connector as defined in claim 9, and further includingprojections extending from opposite edges of said first leg adjacentsaid connecting means, said connecting means including first and secondspaced clamping members respectively adapted to clamp the wire and aninsulating sheath to said strip.